A great many different pump designs are used for transferring and pressurizing fluids. In the context of fuel systems, such as for internal combustion engines, electronically-controlled, high-pressure fuel pumps are commonplace and used to pressurize a fuel such as diesel fuel for injection into an engine cylinder. Highly pressurized fuel injection strategies have been shown to be effective for reduced emissions operation. In one design, a high pressure fuel pump feeds a so-called common rail that provides a fluid reservoir storing a quantity of pressurized fuel for delivery to a plurality of fuel injectors. In other designs, fuel pumps are associated individually with fuel injectors, and are known as unit pumps.
To achieve a high level of control of moving parts within such pumps, electrical actuators such as solenoid actuators are used to control valve positioning and fluid connections. Solenoids produce a magnetic field when electrical current is applied that can generate local forces with sufficient energy to actuate components within the fuel system hardware. Engineers have experimented with a wide variety of different electrical actuator and pump designs over the years. With the drive toward ever-increasing pressure and control over fuel injection amount, fuel injection rate and other properties, the electrical actuators and associated valve components within fuel pumps tend to move relatively rapidly and can impact valve seats, stops, or other surfaces with relatively high forces. One example fuel pump design is known from U.S. Pat. No. 5,743,238 to Shorey et al. In the configuration shown in Shorey et al., an electrical actuator is used to control a valve that apparently varies position to alternately allow or inhibit fuel flow to a pumping chamber.